Provided is a method of manufacturing a semiconductor device which includes, in the following order: a first step of preparing a semiconductor element which includes a pn junction exposure portion; a second step of forming an insulation layer such that the insulation layer covers the pn junction exposure portion; and a third step of forming a glass layer on the insulation layer where a layer made of glass composition for protecting a semiconductor junction is formed on the insulation layer and, thereafter, the layer made of glass composition for protecting a semiconductor junction is baked.